[PATCH v8 29/35] misc/mei/hdcp: Enabling the HDCP authentication

[Ramalingam C]

Request to ME to configure a port as authenticated.

On Success, ME FW will mark the port as authenticated and provides
HDCP cipher with the encryption keys.

Enabling the Authentication can be requested once all stages of
HDCP2.2 authentication is completed by interacting with ME FW.

Only after this stage, driver can enable the HDCP encryption for
the port, through HW registers.

v2:
  Rebased.
v3:
  cldev is passed as first parameter [Tomas]
  Redundant comments and cast are removed [Tomas]
v4:
  %zd for ssize_t [Alexander]
  %s/return -1/return -EIO [Alexander]
  Style and typos fixed [Uma]
v5:
  Rebased.
v6:
  No change.
v7:
  Collected the Rb-ed by.
  Rebased.
v8:
  Adjust to the new mei interface.
  Fix for Kdoc.

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
Reviewed-by: Uma Shankar <uma.shankar at intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 56 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 55 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index 5c7f1e822ed2..08f7310edd68 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -596,6 +596,60 @@ static int mei_verify_mprime(struct device *dev, void *hdcp_data,
 	return 0;
 }
 
+/*
+ * mei_enable_hdcp_authentication :
+ * Function to request ME FW to mark a port as authenticated.
+ *
+ * @dev : device corresponding to the mei_cl_device
+ * @hdcp_data : Intel HW specific hdcp data
+ *
+ * Returns 0 on Success, <0 on Failure
+ */
+static int mei_enable_hdcp_authentication(struct device *dev, void *hdcp_data)
+{
+	struct wired_cmd_enable_auth_in enable_auth_in = { { 0 } };
+	struct wired_cmd_enable_auth_out enable_auth_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	struct mei_hdcp_data *data = hdcp_data;
+	ssize_t byte;
+
+	if (!dev || !data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	enable_auth_in.header.api_version = HDCP_API_VERSION;
+	enable_auth_in.header.command_id = WIRED_ENABLE_AUTH;
+	enable_auth_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	enable_auth_in.header.buffer_len = WIRED_CMD_BUF_LEN_ENABLE_AUTH_IN;
+
+	enable_auth_in.port.integrated_port_type = data->port_type;
+	enable_auth_in.port.physical_port = data->port;
+	enable_auth_in.stream_type = data->streams[0].stream_type;
+
+	byte = mei_cldev_send(cldev, (u8 *)&enable_auth_in,
+			      sizeof(enable_auth_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&enable_auth_out,
+			      sizeof(enable_auth_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (enable_auth_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_ENABLE_AUTH, enable_auth_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
 static __attribute__((unused))
 struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.owner = THIS_MODULE,
@@ -608,7 +662,7 @@ struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.get_session_key = mei_get_session_key,
 	.repeater_check_flow_prepare_ack = mei_repeater_check_flow_prepare_ack,
 	.verify_mprime = mei_verify_mprime,
-	.enable_hdcp_authentication = NULL,
+	.enable_hdcp_authentication = mei_enable_hdcp_authentication,
 	.close_hdcp_session = NULL,
 };
 
-- 
2.7.4